Electric vehicles are well known in the prior art. Two common variations on such vehicles include; purely electric vehicles, also known as, a battery electric vehicle (BEV) having a rechargeable battery and an electric motor for driving the wheels. The other type of vehicle is the Plug-In Hybrid Electric Vehicles (PHEVs) which includes a combination of electric motor and internal combustion engine drive capability for delivering power to the wheels of the vehicle.
One issue common to both the BEVs and PHEVs is an incomplete high voltage (HV) charging of the PHEV and BEV vehicles with multiple low voltage (LV) batteries. The LV batteries are commonly 12.6 volt lead acid batteries connected to a vehicle's low voltage system, but the LV batteries use any battery chemistry. When a fault is detected in one or more of the LV batteries, the charging of the HV battery can be terminated prematurely. An early termination of the HV charging commonly occurs when the LV system detects a fault with one or more LV batteries. This can occur when the 12.6 volt batteries experiences an issue, such as over heating or battery plates touching and shorting out a cell within the battery.
Therefore there is a need for special handling of the low voltage system when one or more of LV batteries are faulted.